How do I Make My Search Bar Search My Website

Google Custom Search (GCS) can be an option, but it searches the whole internet and places large annoying ads in your results. Not to mention, the company is sun-setting GSS (the ad free version).

I would recommend looking into installing a site search plugin like 

- Swiftype or 

- searchIQ. 

Both search ONLY your site and are just much easier and less of a headache to use.